Formation of core-shell nanoparticles under laser ablation of copper and brass in liquids
|Pavel V. Kazakevich 1, Alexander V. Simakin 1, Valeriy V. Voronov 1, Georgy A. Shafeev 1, David Starikov 2,3, Abdelhak Bensaoula 2|
1. General Physics Institute, Vavilov Str. 38, Moscow 117942, Russian Federation
Experimental results are presented on ablation of either copper or brass targets in a liquid environment (e.g., ethanol, acetone, or water) by irradiation with either a pulsed copper vapor laser (0.51 µm) or a pulsed Nd:YAG laser (1.06 µm). The ablated material is ejected into the surrounding liquid in the form of nanoparticles with an average size of 20 nm. The composition of nanoparticles depends on the nature of the liquid. Ablation of brass (40% Zn and 60% Cu) in ethanol results in formation of core-shell nanoparticles. Brass nanoparticles are characterized by a well-pronounced plasmon wavelength peak at 510-520 nm. Under further laser exposure of the colloidal solution the plasmon resonance of the brass nanoparticles shifts to that of pure Cu nanoparticles at 570-590 nm. Ablation of Cu results in formation of shells only in acetone. In a certain range of laser parameters (fluence and number of laser shots) the surface of the solid target is composed of micro-cones having a regular structure. The distance between neighboring micro-cones in the structure depends on the laser fluence and averages around 30 µm. The composition of micro-cones (Cu/Zn ratio) differs from that of the initial surface.
Presentation: poster at E-MRS Fall Meeting 2004, Symposium G, by Pavel V. Kazakevich
See On-line Journal of E-MRS Fall Meeting 2004
Submitted: 2004-06-22 11:40 Revised: 2009-06-08 12:55